;  
; Routine to create an average dark image for
; SwRI images
;

filenm=' '
listfile='./dfedarklist'
pixX = 256
pixY = 1024
bias = fltarr(pixX)
img=intarr(pixX,pixY)
fimg=fltarr(pixX,pixY)
favg=fltarr(pixX,pixY)
 
    close,13 & openr,13,listfile
    ii=0 

loadct,1
 
    close,13 & openr,13,listfile
    ii=0 
    while ( not eof(13) ) do begin & readf,13,filenm & ii=ii+1 & endwhile
    close,13
    numimgs=ii
    print,ii," images"
 
    close,13 & openr,13,listfile

    ii=0 
    while ( not eof(13) ) do begin ;{
        readf,13,filenm
	print,filenm
	close,1 & openr,1,filenm
	img=intarr(pixX,pixY)
	readu,1,img
	byteorder,img
	tv,img*2
	fimg = 1.*img
; Remove electronic intensity to bias on a column basis
	for jj=0,pixX-1 do bias(jj)=fimg(jj,0)
	for jj=0,pixY-1 do fimg(*,jj)=fimg(*,jj)-bias
	favg = favg+1.*img
        ii=ii+1
    endwhile ;} 
 
    close,13
 
    fimg = favg/float(numimgs)
    close,1 & openw,1,'meandark'
    writeu,1,fimg
    close,1
    stop

end